One annoying thing about Yang Kai's personality, which other characters in the story keep pointing out, is his extremely faux humility in front of seniors. Whenever one of them happens to praise him, he's always acting extremely bashfully, downplaying his achievements outrageously. Everyone and their cats and dogs would recognise his words are false and dripping with insincere modesty. The seniors are then forced to try to "convince" him he really is so mighty, and Yang Kai would enjoy it like a five years old boy who could pull off a stunt in front of an endlessly supporting audience of relatives in a friendly family gathering.
Well, maybe this is all a result of the Yang family's original bullshit tradition of sending out their male children out there with no support whatsoever, to survive the best they can, fighting against the odds when other parents are doing their best to help their kids to become strong cultivators. It means the Yang family boys received no love from their parents but instead had to earn every penny on their own like orphans. If they survived, there's an unfortunate possibility of developing a personality that craves the positive attention and acknowledgement they lacked in their childhood. Yang Kai is a living example of this.